1. Field of the Invention
This invention relates to a series of novel aspartic acid analogs which exhibit selective in vitro and in vivo inhibition of interleukin-1.beta. converting enzyme, to compositions containing the novel aspartic acid analogs and to methods for therapeutic utility. More particularly, the interleukin-1.beta. converting enzyme inhibitors described in this invention comprise novel N-(pyrimidinyl)-aspartic acid aldehydes and .alpha.-substituted methyl ketones which possess particular utility in the treatment of inflammatory and immune-based diseases of lung, central nervous system, kidneys, joints, eyes, ears, skin, gastrointestinal tract, urogenital system and connective tissues.
2. Reported Developments
Interleukin-1.beta. (IL-1.beta.) protease (also known as interleukin-1.beta. converting enzyme or ICE) is the enzyme responsible for processing of the biologically inactive 31 kD precursor IL-1.beta. to the biologically active 17 kD form (Kostura, M. J.; Tocci, M. J.; Limjuco, G.; Chin, J.; Cameron, P.; Hillman, A. G.; Chartrain, N. A.; Schmidt, J. A., Proc. Nat. Acad. Sci., (1989), 86, 5227-5231 and Black, R. A.; Kronheim, S. R.; Sleath, P. R., FEBS Let., (1989), 247, 386-391). In addition to acting as one of the body's early responses to injury and infection, IL-1.beta. has also been proposed to act as a mediator of a wide variety of diseases, including rheumatoid arthritis, osteoarthritis, inflammatory bowel disease, sepsis, acute and chronic myelogenous leukemia and osteoporosis (Dinarello, C. A.; Wolff, S. M., New Engl. J. Med., (1993), 328, 106). A naturally occurring IL-1.beta. receptor antagonist has been used to demonstrate the intermediacy of IL-1.beta. in a number of human diseases and animal models (Hannum, C. H.; Wilcox, C. J.; Arend, W. P.; Joslin, G. G.; Dripps, D. J.; Heimdal, P. L.; Armes, L. G.; Sommer, A.; Eisenberg, S. P.; Thompson, R. C., Nature, (1990), 343, 336-340; Eisenberg, S. P.; Evans, R. J.; Arend, W. P.; Verderber, E.; Brewer, M. T.; Hannum, C. H.; Thompson, R. C., Nature (1990), 343, 341-346; Ohisson, K.; Bjork, P.; Bergenfeldt, M.; Hageman, R.; Thompson, R. C., Nature, (1990), 348, 550-552; Wakabayashi, G., FASEB, (1991), 338-343; Pacifici, R.; et al. Proc. Natl. Acad. Sci. (1989), 86, 2398-2402 and Yamamoto, I.; et al. Cancer Rsh (1989), 49, 4242-4246). The specific role of IL-1.beta. in inflammation and immunomodulation is supported by the recent observation that the cowpox virus employs an inhibitor of ICE to suppress the inflammatory response of its host (Ray, C. A. et al, Cell, (1992), 69, 597-604).
In summary, the utility of ICE inhibitors in modifying certain IL-1.beta. mediated disease states has been suggested and demonstrated in vivo by several workers in the field. The following review of the current state of the art in ICE research further supports such utility of ICE inhibitors:
1) WO 9309135, published May 11, 1993, teaches that peptide-based aspartic acid arylacyloxy-and aryoxymethyl ketones are potent inhibitors of ICE in vitro. These compounds also specifically inhibited ICE in the whole cell (in vivo) by their ability to inhibit the formation of mature IL-1.beta. in whole cells. These ICE inhibitors also demonstrated utility in reducing fever and inflammation/swelling in rats. PA0 2) Patients with Lyme disease sometimes develop Lyme arthritis. B. burgdorferi, the causative agent of Lyme disease, is a potent inducer of IL-1 synthesis by mononuclear cells. Miller et al. (Miller, L. C.; Lynch, E. A. Isa, S.; Logan, J. W.; Dinarello, C. A.; and Steere, A. C., "Balance of synovial fluid IL-1.beta. and IL-1 Receptor Antagonist and Recovery from Lyme arthritis", Lancet (1993) 341; 146-148) showed that in patients who recovered quickly from Lyme Arthritis, the balance in synovial fluid of IL-1-beta and IL-1ra was in favor of IL-ra. When the balance was shifted in favor of IL-1.beta., it took significantly longer for the disease to resolve. The conclusion was that the excess IL-1ra blocked the effects of the IL-1.beta. in the patients studied. PA0 3) IL-1 is present in affected tissues in ulcerative colitis in humans. In animal models of the disease, IL-11.beta. levels correlate with disease severity. In the model, administration of 1L-1ra reduced tissue necrosis and the number of inflammatory cells in the colon. PA0 4) IL-1ra supresses joint swelling in the PG-APS model of arthritis in rats. PA0 5) IL-1ra shows efficacy in an small open-label human Rheumatoid Arthritis trial. PA0 6) IL-1 appears to be an autocrine growth factor for the proliferation of chronic myelogenous leukemia cells. Both IL-1ra and sIL-1R inhibit colony growth in cells removed from leukemia patients. PA0 7) As in 6) above, but for acute myelogenous leukemia rather than chronic myelogenous leukemia.
See, Cominelli, F.; Nast, C. C.; Clark, B. D.; Schindler, R., Lierena, R.; Eysselein, V. E.; Thompson, R. C.; and Dinarello, C. A.; "interleukin-1 Gene Expression, Synthesis, and Effect of Specific IL-1 Receptor Blockade in Rabbit Immune Complex Colitis" J. Clin. Investigations (1990) Vol. 86, pp, 972-980. PA1 See Schwab, J. H.; Anderle, S. K.; Brown, R. R.; Dalidorf, F. G. and Thompson, R. C., "Pro- and Anti-Inflammatory Roles of Interelukin-1 in Recurrence of Bacterial Cell Wall-Induced Arthritis in Rats". Infect. Immun. (1991) 59; 4436-4442. PA1 See, Lebsack, M. E.; Paul, C. C.; Bloedow, C. C.; Burch, F. X.; Sack, M. A.; Chase, W., and Catalano, M. A. "Subcutaneous IL-1 Receptor Antagonist in Patients with Rheumatoid Arthritis", Arth. Rheum, (1991) 34; 545. PA1 See, Estrov, Z.; Kurzrock, R.; Wetzler, M.; Kantarjian, H.; Blake, M.; Harris, D.; Gutterman, J. U.; and Talpaz, M., "Supression of Chronic Myelogenous Leukemia Colony Growth by Interleukin-1 (IL-1) Receptor Antagonist and Soluble IL-1 Receptors: a Novel Application for Inhibitors of IL-1 Activity". Blood (1991) 78; 1476-1484. PA1 See, Estrov, Z.; Kurzrock, R.; Estey, E.; Wetzler, M.; Ferrajoli, A.; Harris, D.; Blake, M.; Guttermann, J. U.; and Talpaz, M. "Inhibition of Acute Myelogenous Leukemia Blast Proliferation by Interleukin-1 (IL-1) Receptor Antagonist and Soluble IL-1 Receptors". (1992) Blood 79; 1938-1945. PA1 R.sub.3 and R.sub.4 =independently H, alkyl or aralkyl ##STR6## R.sub.2 =H, alkyl, --(CH.sub.2).sub.0-4 -cycloalkyl, aryl, heteroaryl, aralkyl, heteroaralkyl, --(CH.sub.2).sub.2-4 --R.sub.10 ; PA1 R.sub.1 is defined as: PA1 R.sub.1 --R.sub.4, R.sub.9, R.sub.11, and R.sub.24 are as defined in formula (I), Z is defined as the benzyloxycarbonyl group, W is defined as an OH group, a HNC(H)(CH.sub.2 COOtBu)COCH.sub.2 R.sub.26) and a HNC(H)(CH.sub.2 COOtBu) C.dbd.NNHCONH.sub.2 moieties, where R.sub.26 is defined as F, --O(CO).sub.0-1 -aryl,-OP(O)(R.sub.14)R(.sub.15), ##STR13## wherein R.sub.8, R.sub.14, R.sub.15, R.sub.16, R.sub.17 and R.sub.18 are defined as previously.
Accordingly, disease states in which the ICE inhibitors of Formula I may be useful as therapeutic agents include, but are not limited to, infectious diseases where active infection exists at any body site, such as meningitis and salpingifis; complications of infections including septic shock, disseminated intravascular coagulation, and/or adult respiratory distress syndrome; acute or chronic inflammation due to antigen, antibody, and/or complement deposition; inflammatory conditions including arthritis, cholangitis, colitis, encephalitis, endocarditis, glomerulonephritis, hepatitis, myocarditis, pancreatitis, pericarditis, reperfusion injury and vasculitis. Immune-based diseases which may be responsive to ICE inhibitors of Formula I include but are not limited to conditions involving T-cells and/or macrophages such as acute and delayed hypersensitivity, graft rejection, and graft-versus-host-disease; auto-immune diseases including Type I diabetes mellitus and multiple sclerosis.
All of the inhibitors of ICE described in the art known to Applicants are peptide-based, taking advantage of the substrate specificity of the enzyme. We describe in this invention non-peptide based inhibitors of ICE, specifically where the pyrimidine serves as a recognition surrogate for the P2 and P3 amino acids which up until now had to be present to yield a potent ICE inhibitor (see Structure 1). One well-known advantage of non-peptide inhibitors versus their peptide counterpart is that in vivo metabolism and excretion of such non-peptidic agents to greatly attenuated, thereby leading to enhanced bioavailability of these compounds in animals and humans (Humphrey, M. J. and Ringrose, P. S., "Peptides and Related Drugs: A Review of Their Absorption, Metabolism, and Excretion", Drug Metabolism Reviews, (1986), 17, 283-310. Also Plattner, J. J. and Norbeck, D. W. "Obstacles to Drug Development from Peptide Leads", Drug Discovery Technologies, (1990), Chapter 5, 92-126, C. R. Clark and W. H. Moos, eds.; Horwood: Chichester, U. K. ##STR1##
It should be noted that the pyrimidine-based trifluoromethyl ketones (Structure 2) were recently described as inhibitors of the serene protease, elastase. Since ICE is a cysteine protease and it is known in the prior art that trifluoromethyl ketones are rather poor inhibitors of cysteine proteases (See, Imperialia, B. and Ables, R. H., Biochemistry (1986), 25, 3760-7), it is expected that the pyrimidines of Structure 2 would not be inhibitors of ICE. Also, it is known that ICE requires the aspartic acid side chain (--CH.sub.2 COOH) at PI. Pyrimidines which inhibit elastase (Structure 2) contain the valine side chain (--CHMe.sub.2). In addition, as will be shown later, the pyrimidine-based ICE inhibitors (Structure 1) described in this invention do not inhibit human leucocyte elastase and hence are exquisitely selective for ICE and distinct from the known elastase inhibitors. ##STR2##